Having large amounts of dust in early galaxies, when the Universe was less than a billion years old, could be a challenge for our current understanding of how dust forms and evolves. The lifecycle of dust in intimately related with the lifecycle of stars (Fig. REF ). In the local Universe, one of the main environments for stardust formation is the cool envelope of AGB stars, however, the timescales for these stars to evolve are of the order of 1 billion years or more (i.e., longer than the Hubble time at \(z>6\) ). Based on stellar evolution timescales, at early ages, the main channel for stardust production has to be supernova dust, however the effective dust yields in supernova are still uncertain even in the local Universe. After being formed in stellar envelopes/supernova remnants, dust grows through coagulation and mantle accretion in dense molecular clouds, and although the timescale and efficiency for this process is still debated, models predict that this ISM growth is only efficient once the gas reaches a `critical metallicity' (\(Z_\mathrm {crit}\sim 0.05 - 0.3\,Z_\odot \) ; e.g., [1]}, see also [2]} for a review). For all these reasons, in galaxies at the epoch of reionization (which presumably have young ages and low metallicities), the main source of dust should be supernova stardust (e.g., [3]}).
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